In recent years, coronary intervention has been being performed to treat myocardial infarction and angina pectoris. The coronary intervention is a method of performing treatment by, for example, forming a small hole at the base of a thigh, a wrist, an elbow or the like, inserting a thin tubular treatment instrument, which is called a catheter, through the hole into a blood vessel, and causing the catheter to reach the coronary artery of the heart where abnormality is identified.
In the coronary intervention, an irradiation position (an arm angle, SID (Source Image Distance), and FOV (Field Of View)), and the patient position (the position of a catheter table) are adjusted by an operator, such as a medical doctor or a technician. Consequently, the operator can proceed a maneuver, such as therapy or a test, while appropriately changing the irradiation position and the patient position.
For example, an X-ray diagnostic apparatus has been discussed that uses a catheter and that facilitates grasping a vascular structure around a target site, also facilitates the operation of the catheter, and reduces the test time and the therapeutic time.
In order to reduce exposure to the patient and operator during use of the X-ray diagnostic apparatus, it is desired that an X-ray diaphragm be set at an appropriate position to be irradiated with X-rays every time when the X-ray irradiation position is changed.
Unfortunately, manual setting of the irradiation position and the patient position during the test or therapy by the operator is a burden on the operator. Consequently, such setting is not performed in typical cases.
For example, a method, an apparatus and the like have been discussed that detect the distal end of a device, such as a catheter or a guidewire, and limit the irradiation region in the case where the patient is irradiated.
In the cases of the method and apparatus that limit the irradiation range, it is required to verify not only the distal end of the device to be operated but also the entire coronary artery, for example, whether the catheter provided at the entrance of the coronary artery is off or not, or whether the periphery of the coronary artery is blocked with a floating thrombus. Consequently, the currently discussed method and apparatus are applicable to a test or therapy for a patient only in restricted cases where there is no need to observe the entire coronary artery.
There is a technique referred to as spot fluoroscopy, which allows an operator to diagnose the patient more easily. Also in this case, the irradiation position at which the patient is irradiated with X-rays is required to be set, and it is assumed that not the entire coronary artery is viewable without movement of the X-ray diaphragm along with change in the imaging position.
To address this problem, in a test or therapy, an X-ray diagnostic apparatus is desired that irradiates an irradiation range to be automatically irradiated with X-rays, along with the change in information on the position of the system and the position of the patient during X-ray irradiation to the patient.